Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Statement Of Comprehensive Income [Abstract]
Net earnings	$ 380,112	$ 377,648
Other comprehensive income:
Net unrealized loss on hedging derivatives, net of income taxes of $500 and ($1,000) for the first quarter of 2018 and 2017, respectively	(752)	(1,635)
Reclassification adjustment for settlement of hedging derivatives included in net income, net of income taxes of $0 and $300 for the first quarter of 2018 and 2017, respectively	(48)	485
Foreign currency translation gain, net of income taxes of $0 for both the first quarter of 2018 and 2017	6,115	2,001
Net current-period other comprehensive (loss) income	5,315	851
Comprehensive income	385,427	378,499
Comprehensive income attributable to noncontrolling interests	(25,933)	(20,749)
Comprehensive income attributable to Nucor stockholders	$ 359,494	$ 357,750